Updated for the 2025-2026 flu season

The flu (influenza) is caused by a virus that's easy to spread, especially among kids in school or day care. A child's immune system is not as well developed as an adult's. Also, their lungs and airways are smaller. So, any respiratory viral infection can lead to serious complications. This means that the flu can make children, particularly infants less than 6 months old, very sick. Also, children in day care or school are very likely to bring the virus home to other family members.

Experts strongly advise getting a flu vaccine to protect yourself, your family, and others. Now this is even more important, as flu, COVID-19, and RSV viruses are all likely to spread during flu season. People at high risk for complications from the flu are also likely to be at high risk for serious problems from COVID-19 or RSV, so it's important to get a flu vaccine. Flu vaccines cause antibodies to develop in the body about two weeks after vaccination which provide protection against flu.

Flu symptoms often come on quickly. Symptoms include:

• High fever
• Headache
• Feeling very tired (fatigue)
• Dry cough
• Sore throat
• Runny or stuffy nose
• Muscle aches or body aches
• Acting tired, being fussy, or cranky most of the time

Children may also have upset stomach and vomiting. Some symptoms, such as fatigue and cough, can last many weeks.

A point to remember: "Stomach flu" isn't the flu. It's gastroenteritis (inflammation of the lining of the stomach and intestines).

Here's how you can help your child stay healthy:

• Have your child get a flu vaccine every year, as soon as it's available in your area. This is your child's best chance to prevent the flu. The flu vaccine is recommended every year for babies 6 months and older, children, and teens.
• Teach your child to wash their hands often, the right way: wet, lather, scrub, rinse, and dry. Your child should wash for at least 20 seconds. If your child needs a timer, try humming the "Happy Birthday" song from beginning to end twice. Have your child rinse well and dry using a clean towel.
• Use an alcohol-based hand sanitizer that contains at least 60% alcohol, if soap and water are not available. Always supervise your child when they use hand sanitizer to prevent swallowing alcohol.
• Avoid other people who are sick, when possible.
• Don't let your child drink from the same cup or use eating utensils that others have used. And don't share foods.
• Teach your children to cough or sneeze into their elbow, sleeve, or a tissue. Teach them to wash their hands afterward.

• Give your child plenty of fluids, such as an electrolyte solution, water, juice, and soup.
• Your child can eat foods while having a fever but do not force the child to eat. Often children with flu do better on a bland diet. It is made up of foods that are soft, not very spicy, and low in fiber. You may try:
  • Breads, crackers, and pasta made with refined white flour.
  • Refined hot cereals, such as oatmeal and Cream of Wheat.
  • Fruit juices that are diluted by mixing half water and half juice. Don't give your child too much fruit or apple juice.
• Make sure your child gets plenty of rest.
• Keep your child at home to prevent the spread of germs. Do so until at least 24 hours after the fever is gone.
• Use children's strength medicine for symptoms. Discuss over-the-counter (OTC) medicines with your child's doctor before using them. Note: Don't give OTC cough and cold medicines to a child younger than age 6, unless your child's doctor tells you to do so. Never give children adult medicines.
• Talk to your pharmacist if you have any questions about OTC medicines for your child.
• Don't give your child or teen aspirin. Aspirin can cause a rare but serious condition called Reye syndrome.
• Don't give ibuprofen to an infant age 6 months or younger.
• Ask your child's doctor about antiviral medicine. If taken within the first 2 days of the flu, it can help your child have fewer symptoms and get well sooner.
• Managing Fever: Strictly follow your doctor's instructions about how much and how often you should give the fever medicine. Always check the instructions on the package. You may also follow these tips:
  • Don't bundle up your child with blankets or extra clothes, even if they have the chills. Try one layer of lightweight clothes and a lightweight blanket for sleep.
  • Your child's room should be comfortable, not too hot or too cool. Use a fan at low speed if the room is hot or stuffy.
  • Give a lukewarm bath or sponge bath to help cool the fever.
  • Don't use cold baths, ice, or alcohol rubs. These often cause shivering and can make things worse.

Contact your child's doctor if your otherwise healthy child has:

• Fever (see Fever and children, below)
• Fever with rash
• Seizure
• Trouble breathing or taking feeds
• Symptoms that get worse, or new symptoms, especially after a period of improvement
• Signs of dehydration. These include decreased urination (diapers not as wet as usual in a baby or toddler), dry mouth, and no tears when crying.
• Your child does not act alert or more comfortable when their fever goes down.

Call 911 if your child has:

• Bluish-tinged skin
• Trouble waking up or is not alert
• Severe or continued vomiting

Use a digital thermometer to check your child's temperature. Don't use a mercury thermometer. There are different kinds and uses of digital thermometers. They include:

• Rectal. For children younger than 3 years, a rectal temperature is the most accurate.
• Forehead (temporal). This works for children age 3 months and older. If a child under 3 months old has signs of illness, this can be used for a first pass. The doctor may want to confirm with a rectal temperature.
• Ear (tympanic). Ear temperatures are accurate after 6 months of age, but not before.
• Armpit (axillary). This is the least reliable but may be used for a first pass to check a child of any age with signs of illness. The doctor may want to confirm with a rectal temperature.
• Mouth (oral). Don't use a thermometer in your child's mouth until they are at least 4 years old.

Use a rectal thermometer with care. Follow the product maker's directions for correct use. Insert it gently. Label it and make sure it's not used in the mouth. It may pass on germs from the stool. If you don't feel okay using a rectal thermometer, ask the doctor what type to use instead. When you talk with any doctor about your child's fever, tell them which type you used.

Below is when to contact the doctor if your child has a fever. Your child's doctor may give you different numbers. Follow their instructions.

When to contact a doctor about your child's fever

For a baby under 3 months old:

• First, ask your child's doctor how you should take the temperature.
• Rectal or forehead: 100.4°F (38°C) or higher
• Armpit: 99°F (37.2°C) or higher
• A fever of ___________as advised by the doctor

For a child age 3 months to 36 months (3 years):

• Rectal or forehead: 102°F (38.9°C) or higher
• Ear (only for use over age 6 months): 102°F (38.9°C) or higher
• A fever of ___________ as advised by the doctor

In these cases:

• Armpit temperature of 103°F (39.4°C) or higher in a child of any age
• Temperature of 104°F (40°C) or higher in a child of any age
• A fever of ___________ as advised by the doctor